NEW DELHI - The trial of five men charged with gang-raping and murdering a young woman on a bus in New Delhi opened on Tuesday with closed-door testimony from her male friend who appeared at court in a wheelchair, still bearing the scars of injuries from the attack.

Anindito Mukherjee / EPA

A Delhi police van arrives at the Delhi Saket court in New Delhi, India, Tuesday.

Police allege the six attacked the 23-year-old trainee physiotherapist and her friend on the bus as the couple returned home from watching a movie on Dec. 16.

The woman was repeatedly raped and tortured with a metal bar. The couple were also severely beaten before being thrown onto a road.

The woman died of internal injuries in a Singapore hospital two weeks later.

Victim's father: Hang themAs the trial got under way, the victim's father made a surprise appearance at a news conference organized by the main opposition Bharatiya Janata Party (BJP) to call for his daughter's attackers to be hanged.

At one stage, the friend, defense lawyers and some policemen moved from the courtroom to a courtyard where the bus on which police say the attack took place was parked.

Journalists saw some of them board the vehicle, which was white with tinted windows and orange curtains. Above the windshield was painted "Praise the Goddess" in Hindi.

The victim's friend was not seen boarding the bus. The friend's father said later it was the second time his son had seen the bus since the attack.

Indian authorities have filed rape and murder charges against five men accused of the gang rape of a woman on a New Delhi bus. ITN's Geraint Vincent reports.

In his statement to police after the assault, the friend said their attackers had asked "where are you going with a girl so late at night?" before launching a furious assault in which he was beaten with a metal rod and his clothes ripped off.

While he was being beaten, the woman was repeatedly raped, he said, according to a police charge sheet seen by Reuters.

The prosecution says articles stolen from the couple, including their cellphones, rings and debit cards were found in raids conducted on the homes of the accused. DNA evidence and bloodstained clothes also form part of their case.

Defense lawyers say they will highlight what they say are discrepancies in the account given by the victim's friend.

The five men are being tried in a special fast-track court opposite the shopping mall where the victim and her friend went to watch the film "Life of Pi" before boarding the bus.

About 30 policemen were deployed outside the courtroom on Tuesday as the five accused arrived wearing scarves or handkerchiefs to mask their faces.